Machines for use in manufacturing studs



Aug. 26, 1969 R. F. S|MPSON ET AL MACHINES FOR USE IN'MANUFACTURING STUDS Filed Sept. 11. 1967' 3 Sheets-Sheet 1 IIIUCI'IIOI S I RONALD FRANK SIMPSON FRANK ROBERT SLATER By DANIEL H. KANE Atto rne y Aug. 26, 1969 SIMPSON ET AL 3,462,816

MACHINES FOR USE MANUFACTURING STUDS FiledSept. 11 1967 3 Sheets-Sheet 2 Inventors RONALD FRANK SIMPSON FRANK- ROBERT SLATER By bANIEL H. KAN;

Aflorney a Sheets-Sheet s v lnbenlors RONALD FRANK SIMPSON FRANK ROBERT SLATER DANIEL H. KANE A Home y Aug. 26, 1969 R. F; SIMPSON ET 7 MACHINES FOR USE IN MANUFACTURING STUDS Filed Sept. 11 196.7

United States Patent MACHINES FOR USE IN MANUFACTURING STUDS Ronald Frank Simpson and Frank Robert Slater, Farnham, England, assignors to Dzus Fastener Co., Inc., West Islip, N.Y., a corporation of New York Filed Sept. 11, 1967, Ser. No. 666,665

Int. Cl. B23p 23/04; B23g 9/00 US. Cl. 29-33 17 Claims ABSTRACT OF THE DISCLOSURE A machine for applying a screw driver slot and an identification mark to the head of a stud, such as a fastener or a fastener blank of the type having a shank and a head. The machine has a carrier with holders mounted thereon adapted to grip the shanks of the studs. The carrier is rotated stepwise or intermittently to sequentially bring the holders into adjacent relationship with a loading statlon for loading the studs on the holders, with a press for applying the identification marks to the heads, with a milling head for forming the screw driver slots, and with an ejecting station for ejecting the studs from the holders.

This invention relates to the production of studs which have a shank and head, the head being stamped with an identification mark, such as words or numerals, and being provided with a diametrical screw driver slot. Although the invention is applicable to other studs of the above described kind, we are particularly interested in such studs which are used in conjunction with spring wire retaining members as quick release panel fasteners. In this case the studs are provided at the free ends of their shanks with part helical cam slots for co-operation with the spring wire retaining member.

Conventionally after the blank head and shank of the stud have been prepared the screw driver slot has been milled in the head and the stud has then to be transferred to a fly press where the identification mark has been stamped into the head. This has involved a manual handling operation between the slotting and stamping both in order to clear the swarf from the milled head and to apply the stud to the press in the correct angular orientation so that the identification mark is correctly positioned on each side of the milled slot.

In accordance with the present invention a machine for applying the identification mark and screw driver slot to the head of a stud of the kind described comprises a circular stud carrier which is provided at each of a number of equiangularly spaced positions around its periphery with a holder for gripping the shank of a stud with the head of the stud facing radially outwardly from the carrier, the carrier being rotated about a horizontal axis in a stepwise manner to bring the holders, and in use studs carried by the holders, successively adjacent to a press for stamping the head with the identification mark and then into engagement with a milling cutter for cutting the screw driver slot in the head, and means for ejecting the stamped slotted studs from the holders after the studs have left the milling cutter.

Since the stud heads are stamped before being slotted, the swarf from the milling operation does not interfere with the stamping. The holders grip the shanks of the studs and prevent rotation of the studs in their holders between the stamping and milling operations so that no adjustment has to be made before the screw driver slots are cut. Consequently the machine carries out the two operations quite automatically and speeds of up to 2000 to 2,500 studs per hour throughout can be achieved. Although the studs may be fed into the holders of the carrier 3,462,816 Patented Aug. 26, 1969 manually, an automatic feeding device receiving studs from, for example a vibratory conveyor, which automatically orientates the blank studs and including a ram for inserting the studs into the holes is preferably used.

The carrier may conveniently be in the form of a cylindrical drum, the holders being provided on the cylindrical face of the drum.

The milling cutter may be rotatably mounted on a frame which is pivoted about a horizontal axis whereby the cutter can, in use, be moved towards and away from the carrier as the frame is rocked to and fro about its pivot, for example by a pneumatic ram.

Preferably, a finger rides over a portion of the carrier formed with notches, the finger being arranged to fit into one of the notches and lock the drum against rotation during operation of the press and the cutter and to be removed from the notch as the press is withdrawn to permit the carrier to be rotated. There may then be a safety switch arranged to be operated by the finger to prevent operation of the press or movement of the cutter towards the carrier except when the finger is fitted into one of the notches.

The studs may be removed from the holders after the slotting operation either by a blast of compressed air or a mechanically operated claw, but preferably both are used at subsequent stations so that if a stud is not removed pneumatically, it will be removed by the claw.

One example of a machine according to the invention is shown in the accompanying drawings in which:

FIGURE 1 is an elevation with parts in section;

FIGURE 2 is a plan of the machine with certain parts removed;

EIGURE 3 is an elevation of a part of the machine; an

FIGURE 4 is an elevation of another part of the machine.

In FIGURE 1, a drum 5 is shown, formed with twelve equally spaced, stud carrying dollies 6. The drum is arranged to rotate in steps of 30 in a counter clockwise direction, as seen in FIGURE 1, so that a stud 12 is carried in one of the dollies 6 from the loading station 7, past stamping and slotting stations 8 and 9 respectively to e ecting stations 10 and 11 where it is ejected from the dolly 6.

I At the loading station 7 a loading mechanism 12 conslsts of a stationary tube 13, an outer sliding tube 14, and an inner sliding tube 15 which projects from an open end 16 of the stationary tube 14 where it is formed with a spring collar 17. The outer tube 14 is connected to a pneumatic ram 18 and has a portion 19 projecting through a slot 20 in the stationary tube 13 into a slot 21 in the inner tube 15. A pawl 22 projects from the outer tube 14 across the open end 16 of the stationary tube. The pawl is freely pivoted at 23 and is held in the position shown in FIGURE 1 by its own weight. When the ram 18 is retracted the outer and inner tubes 14 and 15 are drawn upwards over the stationary tube 13. The outer tube moves a short distance before the projecting portion 19 engages the upper end of the slot 21 to move the inner tube. A stud is then released down the stationary tube, lifting and passing beneath the pawl 22 until its shank passes through the collar 17. When the stud is to be loaded into one of the dollies 6, the ram extends, first moving the outer tube downwards relatively to the inner tube so that the pawl 22 presses the head of the stud against the collar causing the shank to project axially of the tubes and then moving the outer and the inner tubes 14 and 15 downwards together to insert the shank into one of the dollies 6 as shown in FIGURE 1. The stud is then moved, by the dolly, circumferentially of the carrier through an opening in the collar 17 and the ram 18 is again retracted in readiness for the next loading operation.

At the stamping station 8 a stamping die 23 formed with an identifying mark, is moved downwards on to the head of stud by an air hydraulic intensifier 24 on receipt of a pneumatic signal. The die is lowered with a predetermined force rather than to a predetermined position so that unavoidable variations in the thickness of the head of the stud will not affect the depth of the impression made by the die. The die remains in contact with the stud head until the air hydraulic intensifier 24 receives a second signal whereupon the die is raised in readiness to stamp the next stud.

At the slotting station 9, a saw blade 25 is rotated continuously on the end of a shaft 26, the other end of which carries a pulley 27 driven by a belt 28 from an electric motor 29. The shaft is held in hearings in a frame 30 which is pivoted about a horizontal axis at 31 and which also carries the motor 29. The frame 30 can be rocked to and fro, to bring the saw against and away from the stud head, by a pneumatic ram 32.

The rocking movement of the frame 30 is limited by two limit switches 33 and 34 shown in FIGURE 2, which are operated by a lug 35 on the rame 30. The switch 33 operates to retract the ram 32 and the switch 34 operates to extend the ram 32 so that the frame oscillates between the two positions in which the limit switches are operated.

As the frame reaches its anti-clockwise limit as shown in FIGURE 1, the saw blade cuts the slot in the stud head and during this portion of its travel, it is necessary that the movement of the saw should be slow and controlled. For this purpose, the frame extends below the shaft 26 where it carries a bolt 36. Immediately before the saw touches the stud head, the bolt 36 bears against a projecting end 37 of a dash pot damper, which is adj usted to allow the ram 32 to move the frame 30 and hence the saw 25 at a suitable rate.

The limit switch 34 which operates to extend the ram 32 also produces the pneumatic signal causing the hydraulic intensifier 24 to lower the die 23 which remains against the stud until the slotting is completed, helping to hold the carrier 5 rigidly in position while the saw 25 cuts the slot in the stud. The switch 33, which operates to retract the ram 32 also produces the pneumatic sig nal which causes the hydraulic intensifier 24 to raise the die 23 and the ram 18 to extend and load a stud into the carrier 6. The ram 18 retracts again after a delay sufficient to allow the stud 12 to be moved through the opening in the collar 17 as the carrier rotates, so that the next stud can be released down the tube 13.

At the ejecting station 10, the stud is ejected by compressed air. For this purpose each of the dollies 6 has a passage 38 leading radially inwards from its inner end and terminating in an axial hole 39 communicating with an end face 40 of the carrier 5. As the dolly 6 reaches the ejection station 10, its hole 39 registers with a compressed air supply 41 shown in dotted lines on FIGURE 1. The stud is thus blown out of the dolly together with any swarf left from the slotting operation. In case this should fail to eject the stud, a pair of resilient claws 42 are moved towards the carrier by a ram 43. The jaws spring over the stud head and, on retraction of the ram 43, positively remove the stud. After removal the stud drops from the jaws 42 which do not grip the stud tightly enough to hold it when unsupported by the dolly.

The mechanism which turns the carrier is shown in FIGURE 3. Twelve ratchet teeth 44 are cut in a shaft 45 which supports the carrier 5. A collar 46 is rotatably mounted on the shaft 45 and has, pivoted on it, a pawl 47 which is urged against the teeth 44 by a spring 48. A rod 49 is connected at one end to the collar 46 by a trunnion 50 and at the other end to a lever 51, the rod being extensible with its two ends urged together by a compression spring 52. The lever 51 is pivoted at 53 on a die holder 54 which is arranged to move with the die 23 and the lever 51 is restrained against vertical movement at the end 55 remote from the rod 52. As the die moves upwards after stamping a stud, the lover is rocked upwards about its end 54 and draws the rod 49 upwards with it. This will normally turn the collar 46 in a clockwise direction as seen in FIGURE 4 and, through the pawl 47 and ratchet teeth 44, the shaft 45 together with the carrier 5. If the carrier is prevented from turning for any reason, the rod 49 will extend against the action of the spring 52 so that no damage is done to the machine.

An arrangement for locating the holder 5 in position, with the dollies and any studs they contain ready for stamping and slotting is shown in FIGURE 4. The carrier 5 has a flange 56 formed with twelve notches 57. A pivoted finger 58 is urged downwards against the flange 56 by a spring 59. When the carrier is turned so that a notch comes beneath the finger 58, the finger snaps into the notch 57, in which it is a close fit, locking the carrier '5 against further rotation. After the slotting and stamping have been completed the stamp holder moves upwards and with it a hook 59 which it carries. As it begins to move upwards, the hook 59 engages the finger 58 lifting it out of the notch 57 and permitting the carrier to turn under the action of the rod 49, pawl 47 and ratchet 44 shown in FIGURE 3. The hook 59 releases the finger 58 before the stamp holder reaches its upward limiting position, thefinger then riding on the flange 56 until snapping into the next notch 57.

A rod 60 is rigidly attached to the finger 58 and projects through an opening 61, in a fixed frame member 62 of the machine, where it is bent and extends beyond the pivotal axis of the finger 58. A safety switch 63 is arranged to be operated by the rod 60 when the finger 58 is seated in one of the notches 57. Except when operated by the rod 60, the switch 63 interrupts the pneumatic signals from the switch 34 to the rams 32 and 43 and the hydraulic intensifier 24, and consequently the slotting, stamping and ejecting operations will only be performed when the carrier 5 is correctly indexed with the finger 58 seated in one of the notches 57.

The flange 56 is bolted to the carrier 5 through elongated holes 64 so that the position of the carrier can be adjusted to bring each of the holders 6 precisely beneath the die 23 when the finger 58 is seated in one of the notches 57. The position of the slotting saw 25 is also adjustable, vertically by an eccentric pivoted hearing at 31, inwardly towards the carrier by moving the eccentric bearing along a slot 64 and axially of the saw by moving a member 65, which supports the frame 30, bodily by means of a bolt 66. Adjustment for the depth of the slot can be made by moving the limit switch 33 inwards towards the hydraulic intensifier 24.

We claim:

1. A machine for applying an identification mark and a screw driver slot to a stud having a head and a shank, said machine comprising a circular stud carrier, a plurality of holders spaced equiangularly about the periphery of said carrier, each of said holders being adapted to grip said shank of said stud with said head of said stud facing radially outward from said carrier, loading means adjacent said carrier for loading said stud into one of said holders, a press angularly spaced round said carrier from said loading means, said press being adapted to stamp said identification mark on said head of said stud, a milling cutter angularly spaced round said carrier from said press, said milling cutter being adapted to cut said slot in said head of said stud, means angularly spaced round said carrier from said milling cutter, for ejecting said stud from said holder, means for mounting said carrier for rotation about a horizontal axis and means for rotating said carrier in a stepwise manner whereby each of said holders is brought in turn adjacent said loading means, said press, said milling cutter and said ejecting means.

2. A machine according to claim 1, wherein said carrier is in the form of a cylindrical drum, said holders being disposed on the cylindrical face of said drum.

3. A machine according to claim 2, wherein said holders are spring collets adapted to receive said shanks of said studs as a push fit.

4. A machine according to claim 2, including a frame pivoted about a horizontal axis said milling cutter being rotatably mounted on said frame whereby said cutter can, be moved towards and away from said carrier as said frame is rocked to and fro about its pivot.

5. A machine according to claim 4, wherein a pneumatic ram is disposed between said pivoted frame and fixed part of said machine to rock said frame to and fro about said pivot.

6, A machine according to claim 5, wherein a dash pot damper is arranged to oppose the action of said pneumatic ram for a portion of the movement of said pivoted frame during which, in use, said cutter cuts said slot in said stud head.

7. A machine according to claim 1, wherein a portion of said carrier is formed with notches and there is a finger arranged to fit into one of said notches whereby said carrier is locked against rotation during operation of said press and said cutter.

8. A machine according to claim 5, including a lug on said pivoted frame, a first limit switch mounted on said fixed part of said machine and adapted to be operated by said lug in a first limiting position of said pivoted frame in which said milling cutter is positioned to cut said slot in said head of said stud, and a second limiting switch adapted to be operated by said lug in a second limiting position by said pivoted frame, operation of said first limit switch causing said pneumatic ram to rock said pivoted frame towards said second limiting position and said operation of second limiting switch causing said pneumatic ram to rock said pivoted frame towards said first limiting position.

9. A machine according to claim 8, wherein said second limit switch also produces a signal which actuates said stamping press, and said first limit switch also produces a signal to release said stamping press.

10. A machine according to claim 7, wherein a safety switch is arranged to be operated by said finger to prevent the operation of said press or movement of said cutter towards said carrier except when said finger is fitted into one of said notches.

11. A machine according to claim 1, wherein the means for rotating said carrier about said horizontal axis in said stepwise manner comprises a ratchet and pawl mechanism.

12. A machine according to claim 11 including a shaft formed with teeth, said carrier being mounted on said shaft, and a pawl, said pawl being arranged to cooperate with said teeth upon raising of said press.

13. A machine according to claim 12, wherein a spring connects said pawl to said press whereby said press will rise against the action of said spring unless said carrier is free to rotate.

14. A machine according to claim 8, wherein said loading means includes a pneumatic ram.

'15. A machine according to claim 14 wherein said loading means is adapted to be actuated by said first limit switch.

16. A machine according to claim 1, wherein said means for ejecting said studs from said carrier comprises a plurality of passages, one passage leading radially inwards from each of said holders, a plurality of openings in said carrier, one of said openings communicating with each of said passages, and a compressed air supply means positioned adjacent to the carrier whereby each of said openings comes in turn into register with said air supply means.

17. A machine according to claim 1, wherein said means for ejecting said studs comprises a claw positioned adjacent said carrier and a ram, said ram being adapted to move said claw towards and away from said carrier.

References Cited UNITED STATES PATENTS 2,929,301 3/1960 Stalhuth 10-6 3,165,765 1/1965 Wilson u 106 RICHARD H. EANES, JR., Primary Examiner U.S. Cl. X.R. l( 6, 11 

